Ser Mandon stands guard during a dinner held by Queen Cersei and Tyrion Lannister in which Cersei reveals Tyrion she has imprisoned his lover/whore. The Queen orders the knight to bring her before them. Ser Mandon and one of his sworn brothers brings in Ros.[3]

Immediately prior to the Battle of the Blackwater Ser Mandon informs Queen Cersei of a groom and two maids attempting to flee with a stolen horse and some gold cups. The Queen orders Ser Mandon to have Ilyn Payne put their heads on spikes outside the stables as a warning.[4]

Tyrion urges a host of men-at-arms to help him fight the invaders and orders Ser Mandon and Ser Boros to join him in leading the battle. Ser Mandon is also ordered to carry the royal banner. In the midst of battle, Ser Mandon attempts to murder Tyrion. He strikes after Tyrion has removed his helmet but only succeeds in cutting his face. Ser Mandon is then killed by Tyrion's squire, Podrick Payne, who drives a lance through the back of his head and out his face.[4]

Gallery

In the books

In the A Song of Ice and Fire novels, Mandon Moore is a member of Robert Baratheon's Kingsguard. Jaime Lannister considers him the most dangerous after himself because his face gives nothing away. In A Clash of Kings, Ser Mandon is not present when Cersei reveals Tyrion she has captured the whore she believes to be his lover. In the books, Ser Mandon is also killed by Podrick Payne, but Pod shoves him into Blackwater Bay as he attempts to assassinate Tyrion Lannister; Moore is dragged underwater by the weight of his armour and drowns.

Unlike his sworn brothers Meryn Trant and Boros Blount, who are regarded as being loyal to the Queen, Ser Mandon's true allegiance remains a mystery and is the subject of speculation. So far, it is unknown who sent him to kill Tyrion.

In the TV series, Tyrion rationalizes that only Cersei or Joffrey could have ordered a Kingsguard to kill him, but even Cersei isn't stupid enough to make such a clumsy assassination attempt: while Joffrey probably hoped that Tyrion's assassination would go unnoticed in the confusion of the battle, it would still have happened in front of his entire army and thus leave dozens of witnesses. Moreover, any witnesses would know that only Cersei or Joffrey could have ordered Ser Mandon, and it would have been more intelligent to order a random sellsword to kill Tyrion than a Kingsguard. On the other hand this hasn't been officially confirmed within the TV series, it is only Tyrion's speculation - it doesn't occur to Tyrion that an allegedly honorable Kingsguard could simply have been corrupted into doing it by almost anyone (i.e. Littlefinger, Varys, etc.).